/*
 * Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: DTM.java,v 1.2.4.1 2005/09/15 08:14:51 suresh_emailid Exp $
 */
package com.sun.org.apache.xml.internal.dtm;

import javax.xml.transform.SourceLocator;

import com.sun.org.apache.xml.internal.utils.XMLString;

/**
 * <code>DTM</code> is an XML document model expressed as a table
 * rather than an object tree. It attempts to provide an interface to
 * a parse tree that has very little object creation. (DTM
 * implementations may also support incremental construction of the
 * model, but that's hidden from the DTM API.)
 *
 * <p>Nodes in the DTM are identified by integer "handles".  A handle must
 * be unique within a process, and carries both node identification and
 * document identification.  It must be possible to compare two handles
 * (and thus their nodes) for identity with "==".</p>
 *
 * <p>Namespace URLs, local-names, and expanded-names can all be
 * represented by and tested as integer ID values.  An expanded name
 * represents (and may or may not directly contain) a combination of
 * the URL ID, and the local-name ID.  Note that the namespace URL id
 * can be 0, which should have the meaning that the namespace is null.
 * For consistancy, zero should not be used for a local-name index. </p>
 *
 * <p>Text content of a node is represented by an index and length,
 * permitting efficient storage such as a shared FastStringBuffer.</p>
 *
 * <p>The model of the tree, as well as the general navigation model,
 * is that of XPath 1.0, for the moment.  The model will eventually be
 * adapted to match the XPath 2.0 data model, XML Schema, and
 * InfoSet.</p>
 *
 * <p>DTM does _not_ directly support the W3C's Document Object
 * Model. However, it attempts to come close enough that an
 * implementation of DTM can be created that wraps a DOM and vice
 * versa.</p>
 *
 * <p><strong>Please Note:</strong> The DTM API is still
 * <strong>Subject To Change.</strong> This wouldn't affect most
 * users, but might require updating some extensions.</p>
 *
 * <p> The largest change being contemplated is a reconsideration of
 * the Node Handle representation.  We are still not entirely sure
 * that an integer packed with two numeric subfields is really the
 * best solution. It has been suggested that we move up to a Long, to
 * permit more nodes per document without having to reduce the number
 * of slots in the DTMManager. There's even been a proposal that we
 * replace these integers with "cursor" objects containing the
 * internal node id and a pointer to the actual DTM object; this might
 * reduce the need to continuously consult the DTMManager to retrieve
 * the latter, and might provide a useful "hook" back into normal Java
 * heap management.  But changing this datatype would have huge impact
 * on Xalan's internals -- especially given Java's lack of C-style
 * typedefs -- so we won't cut over unless we're convinced the new
 * solution really would be an improvement!</p>
 * */
public interface DTM {

    /**
     * Null node handles are represented by this value.
     */
    public static final int NULL = -1;

    // These nodeType mnemonics and values are deliberately the same as those
    // used by the DOM, for convenient mapping
    //
    // %REVIEW% Should we actually define these as initialized to,
    // eg. org.w3c.dom.Document.ELEMENT_NODE?

    /**
     * The node is a <code>Root</code>.
     */
    public static final short ROOT_NODE = 0;

    /**
     * The node is an <code>Element</code>.
     */
    public static final short ELEMENT_NODE = 1;

    /**
     * The node is an <code>Attr</code>.
     */
    public static final short ATTRIBUTE_NODE = 2;

    /**
     * The node is a <code>Text</code> node.
     */
    public static final short TEXT_NODE = 3;

    /**
     * The node is a <code>CDATASection</code>.
     */
    public static final short CDATA_SECTION_NODE = 4;

    /**
     * The node is an <code>EntityReference</code>.
     */
    public static final short ENTITY_REFERENCE_NODE = 5;

    /**
     * The node is an <code>Entity</code>.
     */
    public static final short ENTITY_NODE = 6;

    /**
     * The node is a <code>ProcessingInstruction</code>.
     */
    public static final short PROCESSING_INSTRUCTION_NODE = 7;

    /**
     * The node is a <code>Comment</code>.
     */
    public static final short COMMENT_NODE = 8;

    /**
     * The node is a <code>Document</code>.
     */
    public static final short DOCUMENT_NODE = 9;

    /**
     * The node is a <code>DocumentType</code>.
     */
    public static final short DOCUMENT_TYPE_NODE = 10;

    /**
     * The node is a <code>DocumentFragment</code>.
     */
    public static final short DOCUMENT_FRAGMENT_NODE = 11;

    /**
     * The node is a <code>Notation</code>.
     */
    public static final short NOTATION_NODE = 12;

    /**
     * The node is a <code>namespace node</code>. Note that this is not
     * currently a node type defined by the DOM API.
     */
    public static final short NAMESPACE_NODE = 13;

    /**
     * The number of valid nodetypes.
     */
    public static final short NTYPES = 14;

    // ========= DTM Implementation Control Functions. ==============
    // %TBD% RETIRED -- do via setFeature if needed. Remove from impls.
    // public void setParseBlockSize(int blockSizeSuggestion);

    /**
     * Set an implementation dependent feature.
     * <p>
     * %REVIEW% Do we really expect to set features on DTMs?
     *
     * @param featureId A feature URL.
     * @param state true if this feature should be on, false otherwise.
     */
    public void setFeature(String featureId, boolean state);

    /**
     * Set a run time property for this DTM instance.
     *
     * @param property a <code>String</code> value
     * @param value an <code>Object</code> value
     */
    public void setProperty(String property, Object value);

    // ========= Document Navigation Functions =========

    /**
     * This returns a stateless "traverser", that can navigate over an
     * XPath axis, though not in document order.
     *
     * @param axis One of Axes.ANCESTORORSELF, etc.
     *
     * @return A DTMAxisIterator, or null if the givin axis isn't supported.
     */
    public DTMAxisTraverser getAxisTraverser(final int axis);

    /**
     * This is a shortcut to the iterators that implement
     * XPath axes.
     * Returns a bare-bones iterator that must be initialized
     * with a start node (using iterator.setStartNode()).
     *
     * @param axis One of Axes.ANCESTORORSELF, etc.
     *
     * @return A DTMAxisIterator, or null if the givin axis isn't supported.
     */
    public DTMAxisIterator getAxisIterator(final int axis);

    /**
     * Get an iterator that can navigate over an XPath Axis, predicated by
     * the extended type ID.
     *
     * @param axis
     * @param type An extended type ID.
     *
     * @return A DTMAxisIterator, or null if the givin axis isn't supported.
     */
    public DTMAxisIterator getTypedAxisIterator(final int axis, final int type);

    /**
     * Given a node handle, test if it has child nodes.
     * <p> %REVIEW% This is obviously useful at the DOM layer, where it
     * would permit testing this without having to create a proxy
     * node. It's less useful in the DTM API, where
     * (dtm.getFirstChild(nodeHandle)!=DTM.NULL) is just as fast and
     * almost as self-evident. But it's a convenience, and eases porting
     * of DOM code to DTM.  </p>
     *
     * @param nodeHandle int Handle of the node.
     * @return int true if the given node has child nodes.
     */
    public boolean hasChildNodes(int nodeHandle);

    /**
     * Given a node handle, get the handle of the node's first child.
     *
     * @param nodeHandle int Handle of the node.
     * @return int DTM node-number of first child,
     * or DTM.NULL to indicate none exists.
     */
    public int getFirstChild(int nodeHandle);

    /**
     * Given a node handle, get the handle of the node's last child.
     *
     * @param nodeHandle int Handle of the node.
     * @return int Node-number of last child,
     * or DTM.NULL to indicate none exists.
     */
    public int getLastChild(int nodeHandle);

    /**
     * Retrieves an attribute node by local name and namespace URI
     *
     * %TBD% Note that we currently have no way to support
     * the DOM's old getAttribute() call, which accesses only the qname.
     *
     * @param elementHandle Handle of the node upon which to look up this attribute.
     * @param namespaceURI The namespace URI of the attribute to
     *   retrieve, or null.
     * @param name The local name of the attribute to
     *   retrieve.
     * @return The attribute node handle with the specified name (
     *   <code>nodeName</code>) or <code>DTM.NULL</code> if there is no such
     *   attribute.
     */
    public int getAttributeNode(int elementHandle, String namespaceURI, String name);

    /**
     * Given a node handle, get the index of the node's first attribute.
     *
     * @param nodeHandle int Handle of the node.
     * @return Handle of first attribute, or DTM.NULL to indicate none exists.
     */
    public int getFirstAttribute(int nodeHandle);

    /**
     * Given a node handle, get the index of the node's first namespace node.
     *
     * @param nodeHandle handle to node, which should probably be an element
     *                   node, but need not be.
     *
     * @param inScope true if all namespaces in scope should be
     *                   returned, false if only the node's own
     *                   namespace declarations should be returned.
     * @return handle of first namespace,
     * or DTM.NULL to indicate none exists.
     */
    public int getFirstNamespaceNode(int nodeHandle, boolean inScope);

    /**
     * Given a node handle, advance to its next sibling.
     * @param nodeHandle int Handle of the node.
     * @return int Node-number of next sibling,
     * or DTM.NULL to indicate none exists.
     */
    public int getNextSibling(int nodeHandle);

    /**
     * Given a node handle, find its preceeding sibling.
     * WARNING: DTM implementations may be asymmetric; in some,
     * this operation has been resolved by search, and is relatively expensive.
     *
     * @param nodeHandle the id of the node.
     * @return int Node-number of the previous sib,
     * or DTM.NULL to indicate none exists.
     */
    public int getPreviousSibling(int nodeHandle);

    /**
     * Given a node handle, advance to the next attribute. If an
     * element, we advance to its first attribute; if an attr, we advance to
     * the next attr of the same element.
     *
     * @param nodeHandle int Handle of the node.
     * @return int DTM node-number of the resolved attr,
     * or DTM.NULL to indicate none exists.
     */
    public int getNextAttribute(int nodeHandle);

    /**
     * Given a namespace handle, advance to the next namespace in the same scope
     * (local or local-plus-inherited, as selected by getFirstNamespaceNode)
     *
     * @param baseHandle handle to original node from where the first child
     * was relative to (needed to return nodes in document order).
     * @param namespaceHandle handle to node which must be of type
     * NAMESPACE_NODE.
     * NEEDSDOC @param inScope
     * @return handle of next namespace,
     * or DTM.NULL to indicate none exists.
     */
    public int getNextNamespaceNode(int baseHandle, int namespaceHandle, boolean inScope);

    /**
     * Given a node handle, find its parent node.
     *
     * @param nodeHandle the id of the node.
     * @return int Node handle of parent,
     * or DTM.NULL to indicate none exists.
     */
    public int getParent(int nodeHandle);

    /**
     * Given a DTM which contains only a single document,
     * find the Node Handle of the  Document node. Note
     * that if the DTM is configured so it can contain multiple
     * documents, this call will return the Document currently
     * under construction -- but may return null if it's between
     * documents. Generally, you should use getOwnerDocument(nodeHandle)
     * or getDocumentRoot(nodeHandle) instead.
     *
     * @return int Node handle of document, or DTM.NULL if a shared DTM
     * can not tell us which Document is currently active.
     */
    public int getDocument();

    /**
     * Given a node handle, find the owning document node. This version mimics
     * the behavior of the DOM call by the same name.
     *
     * @param nodeHandle the id of the node.
     * @return int Node handle of owning document, or DTM.NULL if the node was
     * a Document.
     * @see #getDocumentRoot(int nodeHandle)
     */
    public int getOwnerDocument(int nodeHandle);

    /**
     * Given a node handle, find the owning document node.
     *
     * @param nodeHandle the id of the node.
     * @return int Node handle of owning document, or the node itself if it was
     * a Document. (Note difference from DOM, where getOwnerDocument returns
     * null for the Document node.)
     * @see #getOwnerDocument(int nodeHandle)
     */
    public int getDocumentRoot(int nodeHandle);

    /**
     * Get the string-value of a node as a String object
     * (see http://www.w3.org/TR/xpath#data-model
     * for the definition of a node's string-value).
     *
     * @param nodeHandle The node ID.
     *
     * @return A string object that represents the string-value of the given node.
     */
    public XMLString getStringValue(int nodeHandle);

    /**
     * Get number of character array chunks in
     * the string-value of a node.
     * (see http://www.w3.org/TR/xpath#data-model
     * for the definition of a node's string-value).
     * Note that a single text node may have multiple text chunks.
     *
     * @param nodeHandle The node ID.
     *
     * @return number of character array chunks in
     *         the string-value of a node.
     */
    public int getStringValueChunkCount(int nodeHandle);

    /**
     * Get a character array chunk in the string-value of a node.
     * (see http://www.w3.org/TR/xpath#data-model
     * for the definition of a node's string-value).
     * Note that a single text node may have multiple text chunks.
     *
     * @param nodeHandle The node ID.
     * @param chunkIndex Which chunk to get.
     * @param startAndLen  A two-integer array which, upon return, WILL
     * BE FILLED with values representing the chunk's start position
     * within the returned character buffer and the length of the chunk.
     * @return The character array buffer within which the chunk occurs,
     * setting startAndLen's contents as a side-effect.
     */
    public char[] getStringValueChunk(int nodeHandle, int chunkIndex, int[] startAndLen);

    /**
     * Given a node handle, return an ID that represents the node's expanded name.
     *
     * @param nodeHandle The handle to the node in question.
     *
     * @return the expanded-name id of the node.
     */
    public int getExpandedTypeID(int nodeHandle);

    /**
     * Given an expanded name, return an ID.  If the expanded-name does not
     * exist in the internal tables, the entry will be created, and the ID will
     * be returned.  Any additional nodes that are created that have this
     * expanded name will use this ID.
     *
     * NEEDSDOC @param namespace
     * NEEDSDOC @param localName
     * NEEDSDOC @param type
     *
     * @return the expanded-name id of the node.
     */
    public int getExpandedTypeID(String namespace, String localName, int type);

    /**
     * Given an expanded-name ID, return the local name part.
     *
     * @param ExpandedNameID an ID that represents an expanded-name.
     * @return String Local name of this node.
     */
    public String getLocalNameFromExpandedNameID(int ExpandedNameID);

    /**
     * Given an expanded-name ID, return the namespace URI part.
     *
     * @param ExpandedNameID an ID that represents an expanded-name.
     * @return String URI value of this node's namespace, or null if no
     * namespace was resolved.
     */
    public String getNamespaceFromExpandedNameID(int ExpandedNameID);

    /**
     * Given a node handle, return its DOM-style node name. This will
     * include names such as #text or #document.
     *
     * @param nodeHandle the id of the node.
     * @return String Name of this node, which may be an empty string.
     * %REVIEW% Document when empty string is possible...
     */
    public String getNodeName(int nodeHandle);

    /**
     * Given a node handle, return the XPath node name.  This should be
     * the name as described by the XPath data model, NOT the DOM-style
     * name.
     *
     * @param nodeHandle the id of the node.
     * @return String Name of this node.
     */
    public String getNodeNameX(int nodeHandle);

    /**
     * Given a node handle, return its DOM-style localname.
     * (As defined in Namespaces, this is the portion of the name after the
     * prefix, if present, or the whole node name if no prefix exists)
     *
     * @param nodeHandle the id of the node.
     * @return String Local name of this node.
     */
    public String getLocalName(int nodeHandle);

    /**
     * Given a namespace handle, return the prefix that the namespace decl is
     * mapping.
     * Given a node handle, return the prefix used to map to the namespace.
     * (As defined in Namespaces, this is the portion of the name before any
     * colon character).
     *
     * <p> %REVIEW% Are you sure you want "" for no prefix?  </p>
     *
     * @param nodeHandle the id of the node.
     * @return String prefix of this node's name, or "" if no explicit
     * namespace prefix was given.
     */
    public String getPrefix(int nodeHandle);

    /**
     * Given a node handle, return its DOM-style namespace URI
     * (As defined in Namespaces, this is the declared URI which this node's
     * prefix -- or default in lieu thereof -- was mapped to.)
     * @param nodeHandle the id of the node.
     * @return String URI value of this node's namespace, or null if no
     * namespace was resolved.
     */
    public String getNamespaceURI(int nodeHandle);

    /**
     * Given a node handle, return its node value. This is mostly
     * as defined by the DOM, but may ignore some conveniences.
     * <p>
     * @param nodeHandle The node id.
     * @return String Value of this node, or null if not
     * meaningful for this node type.
     */
    public String getNodeValue(int nodeHandle);

    /**
     * Given a node handle, return its DOM-style node type.
     *
     * <p>%REVIEW% Generally, returning short is false economy. Return int?</p>
     *
     * @param nodeHandle The node id.
     * @return int Node type, as per the DOM's Node._NODE constants.
     */
    public short getNodeType(int nodeHandle);

    /**
     * Get the depth level of this node in the tree (equals 1 for
     * a parentless node).
     *
     * @param nodeHandle The node id.
     * @return the number of ancestors, plus one
     * @xsl.usage internal
     */
    public short getLevel(int nodeHandle);

    // ============== Document query functions ==============

    /**
     * Tests whether DTM DOM implementation implements a specific feature and
     * that feature is supported by this node.
     * @param feature The name of the feature to test.
     * @param version This is the version number of the feature to test.
     *   If the version is not
     *   specified, supporting any version of the feature will cause the
     *   method to return <code>true</code>.
     * @return Returns <code>true</code> if the specified feature is
     *   supported on this node, <code>false</code> otherwise.
     */
    public boolean isSupported(String feature, String version);

    /**
     * Return the base URI of the document entity. If it is not known
     * (because the document was parsed from a socket connection or from
     * standard input, for example), the value of this property is unknown.
     *
     * @return the document base URI String object or null if unknown.
     */
    public String getDocumentBaseURI();

    /**
     * Set the base URI of the document entity.
     *
     * @param baseURI the document base URI String object or null if unknown.
     */
    public void setDocumentBaseURI(String baseURI);

    /**
     * Return the system identifier of the document entity. If
     * it is not known, the value of this property is null.
     *
     * @param nodeHandle The node id, which can be any valid node handle.
     * @return the system identifier String object or null if unknown.
     */
    public String getDocumentSystemIdentifier(int nodeHandle);

    /**
     * Return the name of the character encoding scheme
     *        in which the document entity is expressed.
     *
     * @param nodeHandle The node id, which can be any valid node handle.
     * @return the document encoding String object.
     */
    public String getDocumentEncoding(int nodeHandle);

    /**
     * Return an indication of the standalone status of the document,
     *        either "yes" or "no". This property is derived from the optional
     *        standalone document declaration in the XML declaration at the
     *        beginning of the document entity, and has no value if there is no
     *        standalone document declaration.
     *
     * @param nodeHandle The node id, which can be any valid node handle.
     * @return the document standalone String object, either "yes", "no", or null.
     */
    public String getDocumentStandalone(int nodeHandle);

    /**
     * Return a string representing the XML version of the document. This
     * property is derived from the XML declaration optionally present at the
     * beginning of the document entity, and has no value if there is no XML
     * declaration.
     *
     * @param documentHandle the document handle
     * @return the document version String object
     */
    public String getDocumentVersion(int documentHandle);

    /**
     * Return an indication of
     * whether the processor has read the complete DTD. Its value is a
     * boolean. If it is false, then certain properties (indicated in their
     * descriptions below) may be unknown. If it is true, those properties
     * are never unknown.
     *
     * @return <code>true</code> if all declarations were processed;
     *         <code>false</code> otherwise.
     */
    public boolean getDocumentAllDeclarationsProcessed();

    /**
     *   A document type declaration information item has the following properties:
     *
     *     1. [system identifier] The system identifier of the external subset, if
     *        it exists. Otherwise this property has no value.
     *
     * @return the system identifier String object, or null if there is none.
     */
    public String getDocumentTypeDeclarationSystemIdentifier();

    /**
     * Return the public identifier of the external subset,
     * normalized as described in 4.2.2 External Entities [XML]. If there is
     * no external subset or if it has no public identifier, this property
     * has no value.
     *
     * @return the public identifier String object, or null if there is none.
     */
    public String getDocumentTypeDeclarationPublicIdentifier();

    /**
     * Returns the <code>Element</code> whose <code>ID</code> is given by
     * <code>elementId</code>. If no such element exists, returns
     * <code>DTM.NULL</code>. Behavior is not defined if more than one element
     * has this <code>ID</code>. Attributes (including those
     * with the name "ID") are not of type ID unless so defined by DTD/Schema
     * information available to the DTM implementation.
     * Implementations that do not know whether attributes are of type ID or
     * not are expected to return <code>DTM.NULL</code>.
     *
     * <p>%REVIEW% Presumably IDs are still scoped to a single document,
     * and this operation searches only within a single document, right?
     * Wouldn't want collisions between DTMs in the same process.</p>
     *
     * @param elementId The unique <code>id</code> value for an element.
     * @return The handle of the matching element.
     */
    public int getElementById(String elementId);

    /**
     * The getUnparsedEntityURI function returns the URI of the unparsed
     * entity with the specified name in the same document as the context
     * node (see [3.3 Unparsed Entities]). It returns the empty string if
     * there is no such entity.
     * <p>
     * XML processors may choose to use the System Identifier (if one
     * is provided) to resolve the entity, rather than the URI in the
     * Public Identifier. The details are dependent on the processor, and
     * we would have to support some form of plug-in resolver to handle
     * this properly. Currently, we simply return the System Identifier if
     * present, and hope that it a usable URI or that our caller can
     * map it to one.
     * %REVIEW% Resolve Public Identifiers... or consider changing function name.
     * <p>
     * If we find a relative URI
     * reference, XML expects it to be resolved in terms of the base URI
     * of the document. The DOM doesn't do that for us, and it isn't
     * entirely clear whether that should be done here; currently that's
     * pushed up to a higher level of our application. (Note that DOM Level
     * 1 didn't store the document's base URI.)
     * %REVIEW% Consider resolving Relative URIs.
     * <p>
     * (The DOM's statement that "An XML processor may choose to
     * completely expand entities before the structure model is passed
     * to the DOM" refers only to parsed entities, not unparsed, and hence
     * doesn't affect this function.)
     *
     * @param name A string containing the Entity Name of the unparsed
     * entity.
     *
     * @return String containing the URI of the Unparsed Entity, or an
     * empty string if no such entity exists.
     */
    public String getUnparsedEntityURI(String name);

    // ============== Boolean methods ================

    /**
     * Return true if the xsl:strip-space or xsl:preserve-space was processed
     * during construction of the document contained in this DTM.
     *
     * NEEDSDOC ($objectName$) @return
     */
    public boolean supportsPreStripping();

    /**
     * Figure out whether nodeHandle2 should be considered as being later
     * in the document than nodeHandle1, in Document Order as defined
     * by the XPath model. This may not agree with the ordering defined
     * by other XML applications.
     * <p>
     * There are some cases where ordering isn't defined, and neither are
     * the results of this function -- though we'll generally return true.
     * <p>
     * %REVIEW% Make sure this does the right thing with attribute nodes!!!
     * <p>
     * %REVIEW% Consider renaming for clarity. Perhaps isDocumentOrder(a,b)?
     *
     * @param firstNodeHandle DOM Node to perform position comparison on.
     * @param secondNodeHandle DOM Node to perform position comparison on.
     *
     * @return false if secondNode comes before firstNode, otherwise return true.
     * You can think of this as
     * <code>(firstNode.documentOrderPosition &lt;= secondNode.documentOrderPosition)</code>.
     */
    public boolean isNodeAfter(int firstNodeHandle, int secondNodeHandle);

    /**
     * 2. [element content whitespace] A boolean indicating whether a
     * text node represents white space appearing within element content
     * (see [XML], 2.10 "White Space Handling").  Note that validating
     * XML processors are required by XML 1.0 to provide this
     * information... but that DOM Level 2 did not support it, since it
     * depends on knowledge of the DTD which DOM2 could not guarantee
     * would be available.
     * <p>
     * If there is no declaration for the containing element, an XML
     * processor must assume that the whitespace could be meaningful and
     * return false. If no declaration has been read, but the [all
     * declarations processed] property of the document information item
     * is false (so there may be an unread declaration), then the value
     * of this property is indeterminate for white space characters and
     * should probably be reported as false. It is always false for text
     * nodes that contain anything other than (or in addition to) white
     * space.
     * <p>
     * Note too that it always returns false for non-Text nodes.
     * <p>
     * %REVIEW% Joe wants to rename this isWhitespaceInElementContent() for clarity
     *
     * @param nodeHandle the node ID.
     * @return <code>true</code> if the node definitely represents whitespace in
     * element content; <code>false</code> otherwise.
     */
    public boolean isCharacterElementContentWhitespace(int nodeHandle);

    /**
     *    10. [all declarations processed] This property is not strictly speaking
     *        part of the infoset of the document. Rather it is an indication of
     *        whether the processor has read the complete DTD. Its value is a
     *        boolean. If it is false, then certain properties (indicated in their
     *        descriptions below) may be unknown. If it is true, those properties
     *        are never unknown.
     *
     * @param documentHandle A node handle that must identify a document.
     * @return <code>true</code> if all declarations were processed;
     *         <code>false</code> otherwise.
     */
    public boolean isDocumentAllDeclarationsProcessed(int documentHandle);

    /**
     *     5. [specified] A flag indicating whether this attribute was actually
     *        specified in the start-tag of its element, or was defaulted from the
     *        DTD (or schema).
     *
     * @param attributeHandle The attribute handle
     * @return <code>true</code> if the attribute was specified;
     *         <code>false</code> if it was defaulted or the handle doesn't
     *            refer to an attribute node.
     */
    public boolean isAttributeSpecified(int attributeHandle);

    // ========== Direct SAX Dispatch, for optimization purposes ========

    /**
     * Directly call the
     * characters method on the passed ContentHandler for the
     * string-value of the given node (see http://www.w3.org/TR/xpath#data-model
     * for the definition of a node's string-value). Multiple calls to the
     * ContentHandler's characters methods may well occur for a single call to
     * this method.
     *
     * @param nodeHandle The node ID.
     * @param ch A non-null reference to a ContentHandler.
     * @param normalize true if the content should be normalized according to
     * the rules for the XPath
     * <a href="http://www.w3.org/TR/xpath#function-normalize-space">normalize-space</a>
     * function.
     *
     * @throws org.xml.sax.SAXException
     */
    public void dispatchCharactersEvents(int nodeHandle, org.xml.sax.ContentHandler ch, boolean normalize) throws org.xml.sax.SAXException;

    /**
     * Directly create SAX parser events representing the XML content of
     * a DTM subtree. This is a "serialize" operation.
     *
     * @param nodeHandle The node ID.
     * @param ch A non-null reference to a ContentHandler.
     *
     * @throws org.xml.sax.SAXException
     */
    public void dispatchToEvents(int nodeHandle, org.xml.sax.ContentHandler ch) throws org.xml.sax.SAXException;

    /**
     * Return an DOM node for the given node.
     *
     * @param nodeHandle The node ID.
     *
     * @return A node representation of the DTM node.
     */
    public org.w3c.dom.Node getNode(int nodeHandle);

    // ==== Construction methods (may not be supported by some implementations!) =====
    // %REVIEW% What response occurs if not supported?

    /**
     * @return true iff we're building this model incrementally (eg
     * we're partnered with a CoroutineParser) and thus require that the
     * transformation and the parse run simultaneously. Guidance to the
     * DTMManager.
     */
    public boolean needsTwoThreads();

    // %REVIEW% Do these appends make any sense, should we support a
    // wider set of methods (like the "append" methods in the
    // current DTMDocumentImpl draft), or should we just support SAX
    // listener interfaces?  Should it be a separate interface to
    // make that distinction explicit?

    /**
     * Return this DTM's content handler, if it has one.
     *
     * @return null if this model doesn't respond to SAX events.
     */
    public org.xml.sax.ContentHandler getContentHandler();

    /**
     * Return this DTM's lexical handler, if it has one.
     *
     * %REVIEW% Should this return null if constrution already done/begun?
     *
     * @return null if this model doesn't respond to lexical SAX events.
     */
    public org.xml.sax.ext.LexicalHandler getLexicalHandler();

    /**
     * Return this DTM's EntityResolver, if it has one.
     *
     * @return null if this model doesn't respond to SAX entity ref events.
     */
    public org.xml.sax.EntityResolver getEntityResolver();

    /**
     * Return this DTM's DTDHandler, if it has one.
     *
     * @return null if this model doesn't respond to SAX dtd events.
     */
    public org.xml.sax.DTDHandler getDTDHandler();

    /**
     * Return this DTM's ErrorHandler, if it has one.
     *
     * @return null if this model doesn't respond to SAX error events.
     */
    public org.xml.sax.ErrorHandler getErrorHandler();

    /**
     * Return this DTM's DeclHandler, if it has one.
     *
     * @return null if this model doesn't respond to SAX Decl events.
     */
    public org.xml.sax.ext.DeclHandler getDeclHandler();

    /**
     * Append a child to "the end of the document". Please note that
     * the node is always cloned in a base DTM, since our basic behavior
     * is immutable so nodes can't be removed from their previous
     * location.
     *
     * <p> %REVIEW%  DTM maintains an insertion cursor which
     * performs a depth-first tree walk as nodes come in, and this operation
     * is really equivalent to:
     *    insertionCursor.appendChild(document.importNode(newChild)))
     * where the insert point is the last element that was appended (or
     * the last one popped back to by an end-element operation).</p>
     *
     * @param newChild Must be a valid new node handle.
     * @param clone true if the child should be cloned into the document.
     * @param cloneDepth if the clone argument is true, specifies that the
     *                   clone should include all it's children.
     */
    public void appendChild(int newChild, boolean clone, boolean cloneDepth);

    /**
     * Append a text node child that will be constructed from a string,
     * to the end of the document. Behavior is otherwise like appendChild().
     *
     * @param str Non-null reference to a string.
     */
    public void appendTextChild(String str);

    /**
     * Get the location of a node in the source document.
     *
     * @param node an <code>int</code> value
     * @return a <code>SourceLocator</code> value or null if no location
     * is available
     */
    public SourceLocator getSourceLocatorFor(int node);

    /**
     * As the DTM is registered with the DTMManager, this method
     * will be called. This will give the DTM implementation a
     * chance to initialize any subsystems that are required to
     * build the DTM
     */
    public void documentRegistration();

    /**
     * As documents are released from the DTMManager, the DTM implementation
     * will be notified of the event. This will allow the DTM implementation
     * to shutdown any subsystem activity that may of been assoiated with
     * the active DTM Implementation.
     */

    public void documentRelease();

    /**
     * Migrate a DTM built with an old DTMManager to a new DTMManager.
     * After the migration, the new DTMManager will treat the DTM as
     * one that is built by itself.
     * This is used to support DTM sharing between multiple transformations.
     * @param manager the DTMManager
     */
    public void migrateTo(DTMManager manager);
}
